Armor protection must dissipate a projectile's energy and thus prevent total penetration.
Shielding against kinetic energy (KE) projectiles should initially stop or deform the projectiles in order to prevent or limit
penetration. KE survivability considerations include oblique impact, or impact of projectiles at other than a perpendicular angle to
the target surface, which increases the apparent thickness of the armor and decreases the possibility of penetration. The potential
for ricochet increases as the angle of impact from the perpendicular increases.
Improvements in armor technology are becoming much more common worldwide. Many older tanks and armored vehicles are being
retrofitted with improved armor, so it is not just newer vehicles which protection. These advanced armor
configurations improve the vehicles' survivability against all weapons, but for the most
part they are specifically designed to protect against HEAT (high explosive anti-tank ) warheads. This is a complex
technical subject, and growing more so every year, but essentially these improved types
of armor fall into four categories.
-
Reactive Armor. Originally fielded by the Israeli Army, reactive armor appeared
shortly after on enemy tanks. Reactive armor comes in several varieties, but the principle
is essentially the same on all. The armor consists of blocks of explosives sandwiched
between two metal plates and bolted on the outside of the vehicle. Small-arms and
artillery shrapnel will not set off the blocks. However, when a HEAT round strikes the
block, the explosive ignites and blows outwards. The blast and the moving steel plates
disperse and deflect the jet of the HEAT warhead, dramatically reducing its ability to
penetrate armor. Many countries are now fielding different versions of reactive armor.
One of its advantages is that it can easily be retrofitted onto older vehicles.
-
Laminated Armor. Laminated armor was developed in the West, most
specifically by England, the United States, and West Germany. It consists of flat layers of
steel armor plate with layers of ceramics, fiberglass, or other nonmetallic materials in
between. This armor is highly effective against all types of weapons, but is difficult and
expensive to manufacture. Vehicles with laminated armor are characterized by flat, slab
sides, such as on the M1 and Leopard II.
-
Composite Armor. Composite armor consists of a nonmetallic core (usually
some kind of ceramic) around which the rest of the steel of the hull or, more commonly,
the turret, is molded. This is much more effective than conventional steel armor against
all types of weapons, but less so than laminated armor. However, it is less difficult and
expensive to manufacture. Hulls made of composite armor do not have to be slab sided,
like those made of laminated armor.
-
Applique Armor. Applique armor is essentially extra plates mounted or welded
on top of the hull or turret of a vehicle. They can be made of any material, but are
frequently made of ceramic or laminated materials. Like reactive armor, applique armor
is an easy and cost-effective way of improving the protection of older vehicles.